Pen. Code, § 118a

Any person who, in any affidavit taken before any person authorized to administer oaths, swears, affirms, declares, deposes, or certifies that he will testify, declare, depose, or certify before any competent tribunal, officer, or person, in any case then pending or thereafter to be instituted, in any particular manner, or to any particular fact, and in such affidavit willfully and contrary to such oath states as true any material matter which he knows to be false, is guilty of perjury. In any prosecution under this section, the subsequent testimony of such person, in any action involving the matters in such affidavit contained, which is contrary to any of the matters in such affidavit contained, shall be prima facie evidence that the matters in such affidavit were false.